The city of Petra is known throughout the world as a marvel — its buildings are carved directly into towering cliffs, making it look like one of the breathtaking elf cities in Lord of the Rings. And now we know that the builders of this temple, a group known as the Nabateans, knew enough about astronomy to line up their monastery doors perfectly to allow sunlight in on the winter solstice.

When the Earth reaches its farthest point from the sun, light from the sun shines into the monastery — which is located in Petra, Jordan — and falls upon the podium of a deity. At the same time, the light casts the shadow of the head of a lion (a sacred animal in Nabatean culture) upon a mountain opposite to the religious center ...

"The Nabataean monuments are marvelous laboratories where landscape features and the events of the sun, moon and other stars interact," Juan Antonio Belmonte, a researcher at the Canaries Astrophysical Institute and coordinator of the study, said in a statement.